From: Alex Deucher <alexander.deucher@xxxxxxx> - remove adding 2 to checksum, this is incorrect. This was incorrectly introduced in: 92db7f6c860b8190571a9dc1fcbc16d003422fe8 http://lists.freedesktop.org/archives/dri-devel/2011-December/017717.html However, the off by 2 was due to adding the version twice. >From the examples in the URL above: [Rafał Miłecki][RV620] fglrx: 0x7454: 00 A8 5E 79 R600_HDMI_VIDEOINFOFRAME_0 0x7458: 00 28 00 10 R600_HDMI_VIDEOINFOFRAME_1 0x745C: 00 48 00 28 R600_HDMI_VIDEOINFOFRAME_2 0x7460: 02 00 00 48 R600_HDMI_VIDEOINFOFRAME_3 =================== (0x82 + 0x2 + 0xD) + 0x1F8 = 0x289 -0x289 = 0x77 However, the payload sum is not 0x1f8, it's 0x1f6. 00 + A8 + 5E + 00 + 00 + 28 + 00 + 10 + 00 + 48 + 00 + 28 + 00 + 48 = 0x1f6 Bits 25:24 of HDMI_VIDEOINFOFRAME_3 are the packet version, not part of the payload. So the total would be: (0x82 + 0x2 + 0xD) + 0x1f6 = 0x287 -0x287 = 0x79 - properly emit the AVI infoframe version. This was not being emitted previous which is probably what caused the issue above. This should fix blank screen when HDMI audio is enabled on certain monitors. Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Cc: Rafał Miłecki <zajec5@xxxxxxxxx> --- drivers/gpu/drm/radeon/evergreen_hdmi.c | 11 ++--------- drivers/gpu/drm/radeon/r600_hdmi.c | 11 ++--------- 2 files changed, 4 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/radeon/evergreen_hdmi.c b/drivers/gpu/drm/radeon/evergreen_hdmi.c index ed7c8a7..b9c6f76 100644 --- a/drivers/gpu/drm/radeon/evergreen_hdmi.c +++ b/drivers/gpu/drm/radeon/evergreen_hdmi.c @@ -128,14 +128,7 @@ static void evergreen_hdmi_update_avi_infoframe(struct drm_encoder *encoder, struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv; uint32_t offset = dig->afmt->offset; uint8_t *frame = buffer + 3; - - /* Our header values (type, version, length) should be alright, Intel - * is using the same. Checksum function also seems to be OK, it works - * fine for audio infoframe. However calculated value is always lower - * by 2 in comparison to fglrx. It breaks displaying anything in case - * of TVs that strictly check the checksum. Hack it manually here to - * workaround this issue. */ - frame[0x0] += 2; + uint8_t *header = buffer; WREG32(AFMT_AVI_INFO0 + offset, frame[0x0] | (frame[0x1] << 8) | (frame[0x2] << 16) | (frame[0x3] << 24)); @@ -144,7 +137,7 @@ static void evergreen_hdmi_update_avi_infoframe(struct drm_encoder *encoder, WREG32(AFMT_AVI_INFO2 + offset, frame[0x8] | (frame[0x9] << 8) | (frame[0xA] << 16) | (frame[0xB] << 24)); WREG32(AFMT_AVI_INFO3 + offset, - frame[0xC] | (frame[0xD] << 8)); + frame[0xC] | (frame[0xD] << 8) | (header[1] << 24)); } static void evergreen_audio_set_dto(struct drm_encoder *encoder, u32 clock) diff --git a/drivers/gpu/drm/radeon/r600_hdmi.c b/drivers/gpu/drm/radeon/r600_hdmi.c index 456750a..e73b2a7 100644 --- a/drivers/gpu/drm/radeon/r600_hdmi.c +++ b/drivers/gpu/drm/radeon/r600_hdmi.c @@ -133,14 +133,7 @@ static void r600_hdmi_update_avi_infoframe(struct drm_encoder *encoder, struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv; uint32_t offset = dig->afmt->offset; uint8_t *frame = buffer + 3; - - /* Our header values (type, version, length) should be alright, Intel - * is using the same. Checksum function also seems to be OK, it works - * fine for audio infoframe. However calculated value is always lower - * by 2 in comparison to fglrx. It breaks displaying anything in case - * of TVs that strictly check the checksum. Hack it manually here to - * workaround this issue. */ - frame[0x0] += 2; + uint8_t *header = buffer; WREG32(HDMI0_AVI_INFO0 + offset, frame[0x0] | (frame[0x1] << 8) | (frame[0x2] << 16) | (frame[0x3] << 24)); @@ -149,7 +142,7 @@ static void r600_hdmi_update_avi_infoframe(struct drm_encoder *encoder, WREG32(HDMI0_AVI_INFO2 + offset, frame[0x8] | (frame[0x9] << 8) | (frame[0xA] << 16) | (frame[0xB] << 24)); WREG32(HDMI0_AVI_INFO3 + offset, - frame[0xC] | (frame[0xD] << 8)); + frame[0xC] | (frame[0xD] << 8) | (header[1] << 24)); } /* -- 1.7.7.5 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html